CN107530532B

CN107530532B - Device and method for performing a treatment in a tube in the body of a patient

Info

Publication number: CN107530532B
Application number: CN201680020182.6A
Authority: CN
Inventors: 默塔·M·墨菲
Original assignee: Stryker Corp; Stryker European Operations Holdings LLC
Current assignee: Stryker Corp; Stryker European Operations Holdings LLC
Priority date: 2015-02-04
Filing date: 2016-01-08
Publication date: 2022-04-19
Anticipated expiration: 2036-01-08
Also published as: EP3253438B1; ES2932771T3; EP3253438A1; EP3253438A4; CN107530532A

Abstract

Devices and methods for performing therapy within a tube within a body of a patient. According to one embodiment, a treatment catheter is provided having an expandable structure disposed at one end thereof, the catheter including an elongate hollow shaft having one or more first throughbores and one or more second throughbores axially spaced from one another, the one or more first throughbores residing below the expandable structure. A sleeve positioned along an outer surface of the hollow shaft is movable between first and second axial positions to respectively allow or prevent the therapeutic agent from flowing through the one or more second through-holes into a tube within the body. An elongated wire having a sealing unit is disposed within the lumen of the hollow shaft. The sealing unit is movable between a first axial position and a second axial position to respectively allow or prevent flow of an inflation medium between the cavity of the expandable structure and the inner lumen of the hollow shaft through the one or more first through-holes.

Description

Device and method for performing a treatment in a tube in the body of a patient

Cross Reference of Related Applications

This application claims benefit and priority from U.S. provisional application No. 62/112,134 filed on day 4, month 2, 2015.

Technical Field

The present application relates to devices and methods for performing therapy within the vasculature or other bodily duct of a patient.

Disclosure of Invention

According to some embodiments, there is provided a treatment catheter for placement in a tube within a body of a patient, comprising: an expandable structure disposed at one end thereof; an elongate hollow shaft having one or more first through-holes and one or more second through-holes axially spaced from one another, the one or more first through-holes being present below the expandable structure; a sleeve positioned along an outer surface of the elongate hollow shaft, the sleeve being movable between first and second axial positions to respectively allow or prevent a therapeutic agent from flowing through the one or more second through-holes into a tube within the body; and an elongate wire having a sealing unit positioned within the lumen of the elongate hollow shaft, the sealing unit being movable between first and second axial positions to respectively allow or prevent flow of an inflation medium between the cavity of the expandable structure and the lumen of the hollow shaft through the one or more first through holes.

According to some embodiments, there is provided a treatment catheter for placement in a tube within a body of a patient, comprising: an expandable structure capable of assuming an expanded configuration and an unexpanded configuration, the expandable structure comprising a proximal portion and a distal portion, at least the distal portion of the expandable structure adapted to enclose a fluid therethrough when the expandable structure assumes the expanded configuration, the expandable structure having a proximal end and a distal end; an elongate hollow shaft having a proximal portion and a distal portion, the proximal and distal ends of the expandable structure being coupled to the distal portion of the hollow shaft at first and second longitudinal locations, respectively, the second longitudinal location being distal of the first longitudinal location, a wall of the hollow shaft having an inner surface and an outer surface, the inner surface of the wall defining an inner lumen extending between a location at or near the proximal end of the hollow shaft to a location interior of the expandable structure, the hollow shaft having one or more first apertures and one or more second apertures extending through the wall, the one or more first apertures being located adjacent the first longitudinal location, the one or more second apertures being located interior of the expandable structure, between the first and second longitudinal locations; an elongate wire located within the lumen of the hollow shaft and axially movable within the lumen between at least a first axial position and a second axial position, a distal portion of the elongate wire comprising a sealing unit configured to close one or more second apertures in the wall of the hollow shaft when the elongate wire is in the first axial position, the sealing unit being positioned away from the one or more second apertures when the elongate wire is in the second axial position such that the lumen of the hollow shaft is in fluid communication with the internal cavity of the expandable structure; and a sleeve slidable on the outer surface of the hollow shaft between at least a third axial position and a fourth axial position, a distal portion of the sleeve being positioned over the one or more first through holes in the wall of the hollow shaft when in the third axial position to enclose fluid passing through the one or more first through holes, and the sleeve being positioned proximal to the one or more first through holes when in the fourth axial position such that the internal cavity is in fluid communication with the exterior of the hollow shaft.

According to some embodiments, there is provided a method of administering a therapeutic agent to a treatment site in a tube in a patient's body using one of the above-described therapeutic catheters, the method comprising: placing the treatment catheter in a tube within the body such that an entirety of the expandable structure is positioned away from the treatment site; placing the elongate wire at the second axial position; introducing an inflation medium into the proximal end of the inner lumen of the elongate hollow shaft at a sufficient pressure such that the inflation medium flows through the one or more first through-holes to cause the expandable structure to assume the expanded configuration, wherein the expandable structure in the expanded configuration moves the sleeve from the third axial position to the fourth axial position; and introducing the therapeutic agent into the proximal end of the lumen of the hollow shaft with sufficient pressure such that the therapeutic agent flows through the one or more second holes and into the tube within the body.

According to some embodiments, there is provided a method of administering a therapeutic agent to a treatment site in a tube in a patient's body using one of the above-described therapeutic catheters, the method comprising: placing the treatment catheter in a tube within the body such that an entirety of the expandable structure is positioned away from the treatment site; placing the elongate wire at the second axial position; introducing a distending media into the proximal end of the inner lumen of the hollow shaft with sufficient pressure such that the distending media flows through the one or more first apertures to cause the expandable structure to assume the expanded configuration; moving the elongate wire from the second axial position to the first axial position; wherein the elongate wire is in the second axial position and the expandable structure is in the expanded configuration, moving the sleeve from the third axial position to the fourth axial position; and introducing the therapeutic agent into the proximal end of the lumen of the hollow shaft with sufficient pressure such that the therapeutic agent flows through the one or more second holes and into the tube within the body.

According to some embodiments, there is provided a method of removing an obstruction in a tube in a patient's body using one of the above-described treatment catheters, the method comprising: obtaining an intermediate treatment catheter comprising an elongate lumen open at a distal end thereof; advancing the intermediate catheter into a tube within the patient's body such that the open distal end of the elongate lumen is positioned proximate to and adjacent to the obstruction; advancing the treatment catheter through the elongate lumen of the intermediate catheter and into a tube within the body such that the entirety of the expandable structure is positioned away from the obstruction; placing the elongate wire at the second axial position; introducing a distending media into the proximal end of the inner lumen of the hollow shaft with sufficient pressure such that the distending media flows through the one or more first apertures to cause the expandable structure to assume the expanded configuration; wherein the expandable structure in the expanded configuration moves the sleeve from the third axial position to the fourth axial position; introducing the therapeutic agent into the proximal end of the lumen of the hollow shaft with sufficient pressure such that the therapeutic agent flows through the one or more second holes and into the tube within the body; and inhaling at least a portion of the therapeutic agent through the elongate lumen of the intermediate catheter.

According to some embodiments, there is provided a balloon catheter adapted to remove an obstruction in a conduit of a patient, comprising: an elongate catheter having a proximal end, a distal end, and a lumen; and a balloon attached to an outer surface of the elongate catheter, the balloon having an internal cavity in fluid communication with the inner lumen of the elongate catheter, the balloon being inflatable from an unexpanded state to an expanded state and having attached to an outer surface thereof a plurality of proximal extension members configured to pierce the obstruction.

These and other advantages and features will become apparent in view of the drawings and detailed description.

Drawings

Fig. 1 is a cross-sectional view of a treatment catheter according to one embodiment.

Fig. 2A and 2B show cross-sectional views of the treatment catheter of fig. 1, with an elongate wire, in which an integrated sealing unit is provided.

Fig. 3A and 3B show other embodiments in which a sealing unit is attached to the outer surface of the elongate wire.

Figure 4 illustrates a treatment catheter having a sealing unit positioned to allow an inflation medium to flow into an expandable structure of the treatment catheter.

Fig. 5 shows a treatment catheter having a sealing unit positioned to enclose fluid entering an expandable structure and a sleeve positioned to allow a therapeutic agent to flow into a tube within a patient's body.

Fig. 6A and 6B illustrate a manner of locally administering therapy at a location within a vessel within a patient's body.

Figures 7A-D illustrate a treatment system including a treatment catheter and an intermediate catheter.

Fig. 8A illustrates placement of a treatment catheter in a tube within a body with a therapeutic agent infusion port and an expandable structure positioned distal to an obstruction.

FIG. 8B shows the assembly of FIG. 8A, wherein the therapeutic agent is infused into a tube in the body upstream of the obstruction and is inhaled through the intermediary catheter proximal to the obstruction.

Fig. 8C and 8D illustrate a treatment system similar to the system of fig. 8A and 8B, wherein the intermediate catheter is provided with a balloon on its distal end portion.

FIG. 9 illustrates another embodiment of a proximal portion having an expandable structure that includes a porous structure or one or more pores extending therein.

Figure 10 illustrates the diametric relationship between various portions of a treatment catheter according to some embodiments.

FIG. 11 is a flow chart of a method of administering a therapeutic agent to a treatment site in a tube within a patient's body according to one embodiment.

FIG. 12 is a flow chart of a method for removing an obstruction in a tube within a patient's body according to one embodiment.

Fig. 13A-C illustrate a catheter having an expandable structure with a proximal extension member, according to some embodiments.

Fig. 14A illustrates a catheter with a blunt-faced balloon according to one embodiment.

Fig. 14B shows the balloon of fig. 14A with a proximal extension member.

Figures 15A and 15B illustrate an assembly for removing an obstruction from a patient's conduit according to another embodiment.

FIG. 16 is a flow chart of a method for removing an obstruction in a tube within a patient's body, according to one embodiment.

Detailed Description

Fig. 1 shows a cross-sectional view of a treatment catheter 1 according to an embodiment. The treatment catheter 1 comprises an expandable structure 2 having a proximal end 3 and a distal end 4. Each of the proximal and distal ends 3, 4 of the expandable structure 2 is coupled to a distal portion of an elongate hollow shaft 5, the elongate hollow shaft 5 extending along a substantial length of the treatment catheter 1. The expandable structure 2 is capable of assuming an expanded state (as shown) and an unexpanded state, wherein the inner wall of the expandable structure 2 bears against the outer surface 6 of the wall 7 of the elongate outer shaft 5. The expandable structure 2 is generally maintained in an unexpanded state when being delivered or withdrawn through a tube in the body. According to some embodiments, the expandable structure 2 is an inflatable balloon as shown. According to other embodiments, the expandable structure 2 includes a covered expandable and collapsible cage having an internal cavity that can be infused with an inflation medium to effect expansion of the expandable structure. According to some embodiments, in use, the inflation medium comprises a contrast agent that allows visualization of the inflation and/or movement of the expandable structure 2 as it is deployed within the anatomy of the patient. The balloon and cover may comprise any of a variety of known materials capable of fully or at least partially containing the inflation medium within the expandable structure 2 so as to maintain the expandable structure in the expanded state. According to some embodiments, the length of the expandable structure 2 is between 2.0 and 10.0 mm, preferably 2.0 to 5.0 mm.

The elongate hollow shaft 5 includes an inner cavity 10, the inner cavity 10 being defined by the inner surface 8 of the wall 7. According to some embodiments, the elongate hollow shaft 5 has one or more first through holes 11 in the wall 7 underneath the expandable structure 2, said one or more first through holes 11 allowing the inner cavity 10 of the elongate hollow shaft 5 to be in fluid communication with the internal cavity 16 of the expandable structure 2. The elongate hollow shaft 5 further comprises one or more second through-holes 12 located adjacent the expandable structure 2. Covering the one or more second through holes 12 is a sleeve 18, the sleeve 18 being slidable along the outer surface 6 of the elongate hollow shaft 5 between a first axial position, as shown in fig. 1-4A, 6A, 7A, 8A and 9, and a second axial position, as shown in fig. 5, 6B, 7B and 8B. According to some embodiments, a compression fit exists between the inner surface of the sleeve 18 and the outer surface 6 of the elongate hollow shaft 5. As shown in fig. 4, 6A, 7A and 8A, when sleeve 18 is in the first axial position, it is positioned over one or more of second through holes 12 to prevent fluid communication between lumen 10 of elongate hollow shaft 5 and lumen 31 of tube 30 in the body. As shown in fig. 5, 6B, 7B and 8B, when the sleeve 18 is in the second axial position, it does not overlie the one or more second through holes 12 to allow fluid communication between the lumen 10 of the elongate hollow shaft 5 and the lumen 31 of the tube 30 in the body.

According to some embodiments, the elongate hollow shaft 5 comprises a thin-walled, flexible structure that enables the treatment catheter 1 to be delivered through the tortuous anatomy of a patient, such as through the patient's vascular system. According to some embodiments, as shown in fig. 1-4 and 6-8, one or more first and second through-

holes

11 and 12 are formed in the wall 7 of the elongate hollow shaft at discrete locations. According to other embodiments, the one or more first and second through

openings

11 and 12 comprise a subset of a greater number of through openings extending along the main length of the elongate hollow shaft 5, as shown in fig. 4 and 5. The elongate hollow shaft 5 may comprise a polymer, metal, composite material, or any other suitable material suitable for delivering an inflation medium (e.g., saline solution) or a treatment medium (e.g., a drug) through the lumen 10 while imparting the desired flexibility and pushability to the treatment catheter 1 for delivery to a treatment site. According to some embodiments, the elongate hollow shaft 5 is made of metal, such as a metal hypotube. The use of a metallic structure allows the wall 7 of the elongate hollow shaft 5 to have a thinner thickness profile than can be achieved using a polymeric structure. This is advantageous in the following cases: the overall diameter of the treatment catheter 1 is kept to a minimum, such as when used to treat a site located within the neurovascular system of a patient. According to some embodiments, a blade (e.g., a rotating disk) or a laser is used to cut the hypotube to form the one or more first and second through

holes

11 and 12. As shown in fig. 4 and 5, a substantial portion of the length of the hypotube may be cut in a manner that forms a repeating double helix skeleton, which allows the elongate hollow shaft 5 to be flexible in all directions. According to one such embodiment, the proximal portion of the hypotube comprises a solid or substantially solid wall to facilitate pushability, the number of cuts per length increasing along the length of the wall 7 such that the flexibility of the elongate hollow shaft 5 gradually increases along its length in the distal direction. According to one embodiment, the elongate hollow shaft 5 is made of nitinol and has an outer diameter C (see fig. 10) of between about 0.025 and 0.035 inches and a wall thickness of between about 0.0015 and 0.003 inches.

To control the flow of inflation medium into and out of the lumen 16 of the expandable structure 2, the elongate wire 20 is placed within the inner lumen 10 of the elongate hollow shaft 5 while the treatment catheter 1 is being delivered to the treatment site or after the treatment catheter 1 is delivered to the treatment site. In the latter case, the treatment catheter 1 can be guided to the treatment site by using a conventional guide wire. According to some embodiments, a majority of the proximal length 21 of the elongate wire 20, from at or near its proximal end, has an outer diameter a that is less than the inner diameter B of the elongate hollow shaft 5. Such an arrangement allows for the passage of inflation media (see fig. 2B and 4) and/or therapeutic agents (see fig. 5) through the elongate hollow shaft 5. In the embodiment of fig. 2A and 2B, elongate wire 20 further includes a distal segment 22 having an outer surface 25 in sliding engagement with inner surface 8 of elongate hollow shaft 5. In the embodiment of fig. 2A and 2B, the distal segment 22 of the elongate wire 20 constitutes a sealing unit adapted to enclose an inflow of inflation medium into the cavity 16 of the expandable structure 2 when the elongate wire 20 assumes the first axial position as shown in fig. 2A, and further adapted to allow the inflation medium to flow into the cavity 16 of the expandable structure 2 when the elongate wire 20 assumes the second axial position as shown in fig. 2B. According to some embodiments, the outer surface 25 of the distal segment 22 is coated with a hydrophilic coating to enhance the ability of the distal segment to slide along the inner surface 8 of the hollow shaft 5.

As shown, the distal end of the elongate wire 20 may include an end segment that extends distally to the sealing unit. According to some embodiments, the end section comprises an atraumatic distal tip. According to some embodiments, the end section has a length sufficient to self-guide the treatment catheter 1 through at least a portion of a tube within the body.

Fig. 3A shows an alternative embodiment, wherein the sealing unit comprises an elastomeric material 23 positioned around an outer surface 24 of the elongate wire 20. The outer surface 24 may be surface treated (e.g., roughened, coated with an agent to create a tacky surface, etc.) to enhance adhesion of the elastomeric material 23 to the elongate wire 20. The elastomeric material 23 may be present at least partially within the recesses of the elongate wire, as shown in fig. 3B, independent of or in combination with the surface treatment of the outer surface 24 of the elongate wire 20. The elastomeric material may comprise any of a variety of medical grade materials, such as silicone.

According to some embodiments, the elongate wire 20 comprises a hypotube having a lumen extending distally from the proximal end to the distal end portion of the elongate wire. According to such embodiments, the sealing unit may comprise an inflatable membrane (e.g. balloon-like structure) attached to the distal end portion of the elongate wire 20. To this end, the wall of the hypotube may include microchannels for introducing an inflation medium into the internal cavity of the inflatable membrane to effect inflation thereof. Before expansion, the inner wall of the membrane lies against the outer surface of the elongate wire 20. In use, the elongate wire according to such an embodiment may perform two functions. At a time prior to the membrane being expanded, the elongate wire 20 may be used as a conventional guidewire to help guide the treatment catheter 1 through the vasculature in the patient's body to the treatment site. When the treatment catheter 1 is placed at the treatment site, the membrane may be placed inside the lumen 10 of the elongate hollow shaft 5 and subsequently inflated to perform the function of a sealing unit as described above. According to some embodiments, the outer surface of the inflatable membrane is coated with a hydrophilic coating to enhance its ability to slide along the inner surface 8 of the hollow shaft 5. In the embodiment of fig. 3A and 4-8, the distal portion of the elongate wire 20 may have a substantially uniform diameter a ranging between 0.008 inches and 0.012 inches. As described above, when the sealing unit is integral with the elongate wire 20 and forms a single piece with the elongate wire 20, the diameter of the sealing unit portion of the elongate wire 20 is approximately equal to the inner diameter B of the lumen 10 of the elongate wire 20. In such a case, the remaining distal portion of the elongate wire 20 may have a generally uniform or progressively smaller diameter a ranging between 0.008 inches and 0.012 inches.

Fig. 4 shows the treatment catheter with the sleeve 18 in its first axial position and the elongate wire in its second axial position. The sleeve 18 and the elongate wire 20 are positioned such that inflation medium may be delivered through the lumen 10 of the elongate hollow shaft 5 and into the cavity 16 of the expandable structure 2 through one or more first ports 11, as indicated by the arrows in fig. 4. Fig. 5 shows the treatment catheter 1 with the elongate wire 20 in its first axial position and the sleeve 18 in its second axial position. The elongate wire 20 and the cannula 18 are in these respective positions, maintaining the expandable structure 2 in the expanded state, and the therapeutic agent may be delivered through the lumen 10 of the elongate hollow shaft 5 into the lumen 31 of the body tube 30 through the one or more second ports 12.

According to some embodiments, as shown in each of fig. 4 and 5, various components of the treatment catheter 1 may include strategically positioned radiopaque markers to help visualize the location of the various components relative to each other under fluoroscopy. For example, one or more of the distal end of the sleeve 18, the distal end of the expandable structure 2, and the proximal and distal ends of the sealing unit 22 may be provided with radiopaque markers 26.

The catheter systems disclosed herein may be used to administer therapeutic agents locally in a tube within the body of a patient. Treatment may include, but is not limited to, administering a drug to treat vasospasm, administering a drug to treat a diseased wall of a tube within the body, administering a drug or saline solution distally to the obstruction to effect removal or disruption of the obstruction. According to some embodiments, the treatment catheter 1 may be used alone to perform the treatment as shown in fig. 6A and 6B. According to other embodiments, the treatment catheter 1 may be used in conjunction with an intermediate catheter 40, as will be discussed in more detail below with reference to fig. 7 and 8.

The treatment method according to fig. 6A and 6B involves placing the treatment catheter 1 in the body in a tube 30 such that the expandable structure 2 is distal to the site to be treated. As described above, placement of the treatment catheter may occur with or without the elongate wire 20 positioned within the lumen 10 of the elongate hollow shaft 5. In the latter case, the treatment catheter 1 may be guided to the treatment site by using a conventional guide wire. In this case, once the treatment catheter 1 is positioned at or near the treatment site, the conventional guidewire may be removed from the treatment catheter. The elongate wire 20 may then be introduced into the lumen 10 of the elongate hollow shaft 5. In any event, at some point in time after the elongate wire 20 has been positioned in the elongate hollow shaft 5, it is positioned in a second axial position as shown in fig. 2B to allow for the delivery of inflation media into the cavity 16 of the expandable structure 2. As shown in fig. 6A, after the expandable structure 2 is inflated to occlude flow through the tube 30 in the body, the elongate wire 20 is moved to a second axial position to lock the inflation medium within the lumen 16 of the expandable structure 2, thereby maintaining the expandable structure 2 in the expanded state. The therapeutic agent may then be infused into the lumen 31 of the tube 30 within the body by moving the sleeve 18 from its first axial position to its second axial position and passing the therapeutic agent through the lumen 10 of the elongate hollow shaft 5 and through the one or more second throughbores 12, as shown in fig. 6B.

According to some embodiments, the proximal side 50 of the expandable structure 2 comprises a porous material that allows fluid to elute therein. According to other embodiments, as shown in fig. 9, one or more through holes 51 are provided at the proximal side 50 of the expandable structure 2 to allow treatment by infusion thereto. According to each of these embodiments, the therapeutic agent may be delivered to the lumen 31 of the tube 30 in the body only through the proximal side 50 of the expandable structure 2, or through both the expandable structure 2 and one or more second through-holes 12 in the elongate hollow shaft 5. In the latter case, each of the elongate wire 20 and the sleeve 18 are positioned at their respective second axial locations during delivery of the therapeutic agent. When the delivery of the therapeutic agent occurs only through the expandable structure 2, the treatment catheter 1 may be devoid of the sleeve 18 and the one or more second through holes 12.

The treatment method according to fig. 7A and 7B involves the use of a treatment catheter 1 and an intermediate catheter 40. According to some embodiments, the intermediate conduit 40 is an aspiration conduit, as will be discussed in more detail below. Placement of the treatment catheter 1 in the body duct 30 can occur in at least two ways. According to a first method, the treatment catheter 1 is positioned inside the lumen 42 of the intermediate catheter 40 and delivered together to a position close to the intended treatment site. In this case, the distal end 41 of the intermediate catheter 40 and the expandable structure 2 of the treatment catheter 1 are spaced apart from the treatment site located therebetween. Detachment may be performed by advancing the treatment catheter 1 distally of the distal end 41 of the intermediate catheter or by retracting the intermediate catheter 40 proximally away from the expandable structure 2. According to a second method, the intermediate catheter 40 is first placed inside the body of the tube 30 so that its distal end 41 is located near the treatment site. The treatment catheter 1 is then delivered to the treatment site through the lumen 41 of the intermediate catheter 40 such that the expandable structure 2 is located at the distal end of the treatment site. As described above, the distal end 41 of the intermediate catheter 40 and the expandable structure 2 of the treatment catheter 1 are spaced apart from the treatment site located therebetween. As described above, placement of the treatment catheter may occur with or without the elongate wire 20 positioned within the lumen 10 of the elongate hollow shaft 5. When the treatment catheter 1 is delivered to the treatment site without the elongate wire 20, the treatment catheter 1 may be guided to the treatment site using a conventional guide wire that is fed through the lumen 10 of the elongate hollow shaft 5. In this case, once the treatment catheter 1 is located at or near the treatment site, the conventional guide wire may be removed from the treatment catheter. The elongate wire 20 may then be introduced into the lumen 10 of the elongate hollow shaft 5. In any event, at some point in time after the elongate wire 20 has been positioned in the elongate hollow shaft 5, it is positioned in a second axial position as shown in fig. 2B to allow for the delivery of inflation media into the cavity 16 of the expandable structure 2. As shown in fig. 7A, after the expandable structure 2 is inflated to occlude flow through the tube 30 in the body, the elongate wire 20 is moved to a second axial position to lock the inflation medium within the lumen 16 of the expandable structure 2 to maintain the expandable structure 2 in the inflated state. The therapeutic agent may then be infused into the lumen 31 of the body tube 30 by moving the sleeve 18 from its first axial position to its second axial position and delivered through the lumen 10 of the elongate hollow shaft 5 and through the one or more second throughbores 12, as shown in fig. 7B.

According to some embodiments, the intermediate catheter 40 has a balloon 45 disposed on a distal portion thereof. In some cases, as shown in fig. 7C and 7D, a balloon 45 is disposed near the distal end 41 of the intermediate catheter 40. During delivery of the intermediate catheter to the treatment site, the balloon 45 is normally in an uninflated state and then inflated to prevent the therapeutic agent from flowing proximal to the balloon. In this way, according to some embodiments, the treatment site is located between the balloon 45 of the intermediate catheter 40 and the expandable structure 2. Although not shown in fig. 7C and 7D, the intermediate catheter 40 has an inflation lumen to facilitate delivery of an inflation medium to the interior of the balloon 45. According to other embodiments (not shown in the figures), a balloon guide catheter may be used to assist in the placement of the treatment catheter 1 at the treatment site. In such embodiments, the balloon located near the distal end of the guide catheter may function in the same manner as balloon 45 described above to create a treatment area located between the balloon of the treatment catheter and the expandable structure 2. The balloon guide catheter may be used with or without the intermediate catheter 40.

With continued reference to fig. 7B, according to some embodiments, the intermediate catheter 40 may also be used as a suction catheter, thereby establishing a negative pressure in the lumen 42 by applying suction at its proximal portion. Use of the intermediate catheter 40 in this manner facilitates local and non-systemic delivery of the therapeutic agent into the tube 30 within the body due to all or most of the therapeutic agent removed through the intermediate catheter 40.

Figures 8A and 8B illustrate a treatment catheter 1 for use with an intermediary catheter 40 to effect at least partial removal of an obstruction 60 that completely or partially occludes a portion of a tube 30 within a body. The obstruction 60 may be, for example, a blood clot located in the vascular system of a patient. The placement of each of the intermediate catheter 40 and the treatment catheter 1 may be performed in a manner consistent with those described above in connection with fig. 7. Once the treatment catheter 1 and the intermediate catheter 40 have been placed in their respective positions within the body tube 30, as shown in fig. 8A, the treatment agent may be introduced into the lumen 10 of the elongate hollow shaft 5 and the sleeve 18 moved to its second axial position to effect flow of the treatment agent into the lumen 31 of the body tube 30, as shown in fig. 8B. As with the previous embodiment, the therapeutic agent is administered at a pressure sufficient to establish reflux, as indicated by the arrows in fig. 8B. The therapeutic agent may be a drug that induces disruption of obstruction 60. When obstruction 60 is a blood clot, the therapeutic agent can be, for example, a tissue plasma activating drug. According to other methods, the therapeutic agent may simply be a saline solution, and in some cases may be the same saline solution used to inflate the expandable structure 2.

According to some embodiments, the intermediate catheter 40 has a balloon 45 disposed on a distal portion thereof. In some cases, as shown in fig. 8C and 8D, a balloon 45 is disposed near the distal end 41 of the intermediate catheter 40. During delivery of the intermediate catheter to the treatment site, the balloon 45 is normally in an uninflated state and then inflated to prevent the therapeutic agent from flowing proximal to the balloon. In this manner, according to some embodiments, the obstruction 60 is located between the balloon 45 of the intermediate catheter 40 and the expandable structure 2. Although not shown in fig. 8C and 8D, the intermediate catheter 40 has an inflation lumen to facilitate delivery of an inflation medium to the interior of the balloon 45. According to other embodiments, a balloon guide catheter, not shown in the figures, may be used to assist in placement of the treatment catheter 1 at the treatment site adjacent the obstruction 60. In such embodiments, the balloon located near the distal end of the guide catheter may function in the same manner as balloon 45 described above to isolate obstruction 60 between the balloon and the expandable structure 2 of the treatment catheter. The balloon guide catheter may be used with or without the intermediate catheter 40.

According to embodiments involving the use of the intermediate catheter 40, the ratio of the inner diameter D of the intermediate catheter lumen 42 to the outer diameter C of the elongate hollow shaft 5 (ratio D/C) may be between 1.5 and 5.0, preferably between 2.0 and 4.0.

Although not shown in the drawings, one or more of the elongate hollow shaft 5, the sleeve 18, and the elongate wire 20 may include one or more stop elements for limiting movement between the various components. For example, according to some embodiments, a stop is provided to limit the movement of the sleeve 18 between its first and second axial positions. Further, one or more stops may be provided to limit distal advancement of the elongate wire 20 to a position such as that shown in fig. 2B. According to some embodiments, one or more stops are further provided to limit proximal movement of the elongate wire 20 to a position such as that shown in fig. 2A.

After the treatment procedure is completed, it is necessary to at least partially collapse the expandable structure 2 in order to facilitate removal of the treatment catheter 1 from the patient. One method is to position the elongate wire 20 at its second axial position to allow the inflation medium to flow into the lumen 10 of the elongate hollow shaft 5. In some cases, suction is applied to the proximal end of the inner lumen 10 to facilitate extraction of inflation media from the cavity 16 of the expandable structure 2. According to other embodiments, collapsing is achieved by placing each of the sleeve 18 and the elongate wire 2 in its respective second axial position to establish an inflation medium flow path between the cavity 16 and the inner lumen 31 of the tube 30 within the body. According to other embodiments, the elongate wire 20 may be advanced distally a distance to establish a flow path between the lumen 16 and the inner lumen 31 of the in vivo tube 30 through the distal end of the elongate hollow shaft 5.

An expandable assembly (e.g., balloon) may also provide protection when in an expanded state, preventing emboli from traveling away from a treatment site, according to any of the methods disclosed herein. The expandable structure may also be used to remove an obstruction by proximally retracting the expandable structure after it assumes an expanded state to remove the obstruction. Further, at any given time during the removal of an obstruction, contrast agent may be infused through the one or more second ports 12 to aid in visualization of the removal of the obstruction.

Fig. 11 is a flow chart of a method of administering a therapeutic agent at a treatment site of a tube 30 within a patient's body. At step 100, the treatment catheter is placed within the inner lumen 31 of the body tube 30 such that the entire expandable structure 2 is located distal to the treatment site. At step 101, the elongate wire 20 is moved to its second axial position if it is not already in its second axial position. At step 102, an inflation medium is introduced into the proximal end of the inner lumen 10 of the elongate hollow shaft 5 with sufficient pressure to cause the inflation medium to flow through the one or more first through holes 11 of the elongate hollow shaft 5 to cause the expandable structure 2 to assume the expanded configuration. At step 103, the expandable structure is in an expanded configuration with the sleeve moved from its first axial position to its second axial position. During the step of introducing the therapeutic agent into the proximal end of the lumen 10 of the elongate hollow shaft 5, the therapeutic agent is caused to flow through the one or more second holes 12 of the elongate hollow shaft 5 and into the lumen 31 of the body tube 30 with sufficient pressure.

FIG. 12 is a flow chart of a method for removing an obstruction 60 in a tube 30 in a patient. At step 200, an intermediate catheter 40 is obtained, which includes an elongated lumen 42 open at its distal end 41. At step 201, the intermediate catheter 40 is introduced into a tube within the body of the patient such that the open distal end 41 of the elongate lumen 42 is positioned adjacent and proximal to the obstruction 60. At step 202, the treatment catheter is passed through the elongate lumen 42 of the intermediate catheter 40 and into the tube 30 within the body such that the entirety of the expandable structure 2 is present distal of the obstruction 60. At step 203, if the elongate wire 20 is not already in its second axial position, the elongate wire 20 is moved to its second axial position. At step 204, an inflation medium is introduced into the proximal end of the inner lumen 10 of the elongate hollow shaft 5 with sufficient pressure to cause the inflation medium to flow through the one or more first holes 11 of the elongate hollow shaft 5 to cause the expandable structure 2 to assume the expanded configuration. At step 205, the expandable structure 2 is in an expanded configuration, moving the sleeve 18 from its first axial position to its second axial position. At step 206, the therapeutic agent is introduced into the proximal end of the lumen 10 of the elongate hollow shaft 5 with sufficient pressure so that the therapeutic agent flows through the one or more second holes 12 of the elongate hollow shaft 5 and into the tube 30 within the body. At step 207, at least a portion of the therapeutic agent is aspirated through the elongate lumen 42 of the intermediate catheter 40.

Figures 15A and 15B illustrate an assembly for removing an obstruction 60 from a tube 30 within a patient's body according to another embodiment. The assembly includes a treatment catheter 1 similar to that disclosed above for removing obstructions 60 at least partially through one or more second ports 12 by applying suction pressure at the proximal end of the treatment catheter. FIG. 16 is a flow chart of a method of removing an obstruction 60 by using the assembly. At step 300, the treatment catheter 1 is placed at the treatment site such that the expandable assembly 2 is present downstream of the obstruction 60 and such that the one or more second vents 12 are present inside the obstruction. At step 301, expandable assembly 2 is expanded according to any of the methods previously described herein. At step 302, the sleeve 18 is retracted proximally to place the inner lumen 10 of the elongate hollow shaft 5 in communication with the interior of the obstruction 60 via the one or more second ports 12. At step 303, which may occur before or after step 302, sufficient suction pressure is applied at the proximal end of elongate hollow shaft 5 to at least partially remove obstruction 60 from lumen 31 of tube 30 within the body. According to some embodiments, once the obstruction 60 is at least partially removed from the blood vessel 30, a further step 304 is employed which involves proximally retracting the treatment catheter 1 such that the expandable structure 2 engages the obstruction 60 to push it proximally into the intermediate catheter 40, as described above, or the obstruction 60 may be pushed into another proximal location where it can be removed from the lumen 31 of the tube 30 within the body.

As noted above, the expandable structure 2 (e.g., balloon) may be used to remove the obstruction by proximally retracting the expandable structure after it assumes the expandable structure. When using a balloon or cage-like structure, a problem associated with removing blood clots or other obstructions of the vessel within the body is that the obstruction rolls along the outer surface of the balloon or cage as the balloon or cage is moved proximally in an attempt to remove the obstruction. According to some embodiments, as shown in fig. 13A and 13B, a plurality of proximal extension members 55 are attached to the outer surface of the expandable structure 2, these components help anchor the obstruction to the expandable structure 2 as the expandable structure moves proximally into engagement with the obstruction. That is, the proximal extension member 55 is adapted (with sufficient rigidity) to penetrate at least a portion of the obstruction 60 when the expandable assembly 2 is advanced in the proximal direction to engage the obstruction 60. By sandwiching the obstructions between themselves and the leading outer surface of the expandable assembly 2, the proximal extension members 55 minimize the likelihood of the obstruction rolling on the expandable assembly 2 as it is advanced proximally distal of the obstruction. Fig. 13A and 13B illustrate the use of 2 and 4 proximal extension members 55, respectively. However, it should be understood that any number of proximal extension members 55 may be employed. According to some embodiments, the proximally extending members are equally spaced around the circumference of the expandable assembly 2. Proximal extension member 55 may comprise any of a variety of medical grade materials, including but not limited to metals (e.g., nitinol) and low elasticity polymers (e.g., polyetheramides).

According to some embodiments, as shown in fig. 13C, all or at least some of the proximal extension members 55 are oriented on the expandable structure 2 in such a way as to slope downwardly toward the center of the catheter when the expandable structure 2 assumes its expanded configuration. The downward slope reduces the risk of the proximally extending member 55 adversely interfering with or piercing the luminal wall of the blood vessel under treatment.

According to some embodiments, at least the leading outer surface 56 of the expandable structure 2 may alternatively or in combination be surface treated or coated with a compound using the proximal extension member 55 to increase its surface roughness.

According to some embodiments, as shown in FIG. 14A, expandable assembly 2 is a balloon configured with a blunt leading surface 57 opposite the sloped curvilinear surface shown in the previous embodiments. Blunt leading surface 57 may be generally vertical or may have an inclination angle of less than 10 degrees, preferably less than 5 degrees. The blunt surface feature may be incorporated into any of the embodiments disclosed or contemplated herein. One particular advantage of the blunt leading surface 57 is that it accommodates a small amount of obstruction 60 in allowing the obstruction 60 to roll on the outer surface of the balloon 2 when the balloon is used to remove the obstruction. Similar to the embodiment of fig. 13A and 13B, the blunt balloon of fig. 14A may further include a proximal extension member 55, as shown in fig. 14B, to help anchor the obstruction 60 to the balloon 2 when it is used to remove the obstruction. At least the blunt surface 57 of the balloon 2 may also be surface treated or coated with a compound to increase its surface roughness.

The particular features, structures, or characteristics of any of the embodiments described above may be combined in any suitable manner, as would be apparent to one skilled in the art from this disclosure, in one or more embodiments. Similarly, it should be appreciated that in the foregoing description of embodiments, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that any claim requires more features than are expressly recited in that claim. Rather, inventive aspects lie in less than all features of any single foregoing disclosed embodiment. Detailed description the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment.

Claims

1. A treatment catheter for placement in a tube within a body of a patient, the treatment catheter comprising:

the structure of the expandable structure is provided with a plurality of expansion joints,

an elongate hollow shaft having a wall with one or more first through holes and one or more second through holes, the one or more first through holes being axially spaced from the one or more second through holes, the elongate hollow shaft having a proximal end portion and a distal end portion, the expandable structure being disposed around the distal end portion of the elongate hollow shaft such that the one or more first through holes are located within the expandable structure and the one or more second through holes being positioned proximal to and proximate to the expandable structure,

a sleeve positioned along an outer surface of the elongate hollow shaft and movable between a first axial position and a second axial position, wherein the sleeve at the first axial position prevents the therapeutic agent from flowing through the one or more second through-holes into the tubes within the body and the sleeve at the second axial position allows the therapeutic agent to flow through the one or more second through-holes into the tubes within the body such that the therapeutic agent forms a reverse flow after entering the tubes within the body opposite the direction of flow of the therapeutic agent within the elongate hollow shaft,

an elongate wire having a sealing unit positioned within the inner lumen of the elongate hollow shaft, the sealing unit positioned at least partially below the expandable structure and movable between a first axial position and a second axial position, wherein the elongate wire at the first axial position prevents flow of inflation media between the cavity of the expandable structure and the inner lumen of the elongate hollow shaft through the one or more first through holes and the elongate wire at the second axial position allows flow of inflation media between the cavity of the expandable structure and the inner lumen of the elongate hollow shaft through the one or more first through holes, the first axial position being located proximate to the second axial position.

2. The treatment catheter according to claim 1, wherein a cross-sectional area of the elongate wire at the proximal end of the sealing unit is smaller than a cross-sectional area of the lumen of the elongate hollow shaft.

3. The treatment catheter according to claim 1, wherein the elongate hollow shaft is made of metal.

4. The treatment catheter according to claim 3, wherein the elongate hollow shaft is a metal hypotube.

5. The treatment catheter according to claim 3, wherein the elongate hollow shaft has an outer diameter of between 0.0635cm and 0.0889 cm.

6. The treatment catheter according to claim 5, wherein the wall of the elongate hollow shaft has a thickness of between 0.00381cm and 0.00762 cm.

7. The treatment catheter according to claim 5, wherein a plurality of cuts extending medially from the outer surface are provided at the distal portion of the elongate hollow shaft to enhance flexibility of the distal portion.

8. The treatment catheter according to claim 1, wherein there is a compression fit between an outer surface of the sealing unit and an inner surface of the elongate hollow shaft.

9. The treatment catheter according to claim 1, wherein there is a compression fit between the sleeve and an outer surface of the elongate hollow shaft.

10. The treatment catheter according to claim 1, wherein an elastomeric material is present in the sealing unit partially along the length of the outer surface of the elongated wire, wherein the elastomeric material is present within a recess in the outer surface of the elongated wire.

11. The treatment catheter according to claim 10, wherein an outer surface of the elongate wire is roughened to enhance adhesion of the elastomeric material to the elongate wire.

12. The treatment catheter according to claim 1, wherein the sealing unit includes a proximal end and a distal end, and the elongate wire is provided with a first radiopaque marking adjacent the proximal end of the sealing unit and a second radiopaque marking adjacent the distal end of the sealing unit.

13. The treatment catheter according to claim 12, wherein a distal end of the sleeve is provided with a third radiopaque marking.

14. The treatment catheter according to claim 1, wherein one or more of the elongate hollow shaft and the elongate wire are provided with a stop element to limit axial movement of the sealing unit between a first axial position and a second axial position.

15. The treatment catheter according to claim 1, wherein the elongate wire includes an end segment extending distally to the sealing unit, the end segment having a length sufficient for the treatment catheter to be self-guided through at least a portion of a tube within the body.

16. The treatment catheter according to claim 1, wherein the expandable structure is a balloon including an inflatable membrane.

17. The treatment catheter of claim 16, wherein at least a portion of the inflatable membrane positioned along the proximal portion of the balloon is porous.